What is the first line of treatment for a patient experiencing a seizure?

First-Line Treatment for Active Seizures

Administer intravenous lorazepam 4 mg at 2 mg/min immediately for any patient actively seizing—this is the definitive first-line treatment with Level A evidence and 65% efficacy in terminating status epilepticus. 1, 2

Immediate Actions (Within First 60 Seconds)

• Check fingerstick glucose immediately and correct hypoglycemia while administering lorazepam, as this is a rapidly reversible cause 1
• Have airway equipment at bedside before administering lorazepam, as respiratory depression can occur 1, 2
• Establish IV access if available—this is the preferred route for benzodiazepine administration 3

First-Line Treatment Algorithm

If IV Access Available:

• Lorazepam 4 mg IV at 2 mg/min is preferred over diazepam (59.1% vs 42.6% seizure termination rate) 1
• If seizures continue after 10-15 minutes, give a second dose of lorazepam 4 mg IV 2
• Lorazepam has a longer duration of action than diazepam, making it superior for sustained seizure control 1

If IV Access NOT Available:

• Administer rectal diazepam as the recommended alternative 3
• Intramuscular midazolam is non-inferior to IV lorazepam and should be considered when IV access is difficult 1, 4
• Never use intramuscular diazepam due to erratic absorption 3
• IM phenobarbital may be considered only when rectal diazepam is not possible due to medical or social reasons 3

Critical Monitoring During Benzodiazepine Administration

• Continuous respiratory monitoring is mandatory, with readiness to provide ventilatory support 2, 5
• Monitor blood pressure and cardiac status, particularly in elderly or debilitated patients 2
• Inject slowly over at least 1 minute per 5 mg to minimize cardiovascular and respiratory complications 2

Second-Line Treatment (If Seizures Continue After Adequate Benzodiazepines)

If the patient continues seizing after two doses of lorazepam, immediately escalate to one of these second-line agents:

Preferred Second-Line Options (in order of preference):

1. Valproate 20-30 mg/kg IV over 5-20 minutes: 88% efficacy with 0% hypotension risk—superior safety profile 1, 6

2. Levetiracetam 30 mg/kg IV over 5 minutes: 68-73% efficacy with minimal cardiovascular effects, no cardiac monitoring required 1, 6

3. Fosphenytoin 20 mg PE/kg IV at maximum 50 mg/min: 84% efficacy but 12% hypotension risk, requires continuous ECG and blood pressure monitoring 1, 6

4. Phenobarbital 20 mg/kg IV over 10 minutes: 58.2% efficacy but higher risk of respiratory depression 6

Critical Pitfalls to Avoid

• Never use carbamazepine for acute seizure termination—it has no role in status epilepticus and is not mentioned in any treatment guidelines 1
• Never use neuromuscular blockers alone (such as rocuronium)—they only mask motor manifestations while allowing continued electrical seizure activity and brain injury 6, 7
• Never delay anticonvulsant administration for neuroimaging in active status epilepticus—CT scanning can be performed after seizure control 1
• Never skip directly to third-line agents (pentobarbital, propofol) until benzodiazepines and a second-line agent have been tried 6

Simultaneous Evaluation for Reversible Causes

While administering treatment, immediately search for and correct these underlying causes: 1, 6

• Hypoglycemia (check fingerstick glucose)
• Hyponatremia and other electrolyte abnormalities
• Hypoxia
• Drug toxicity or withdrawal syndromes (especially alcohol, benzodiazepines)
• CNS infection (meningitis, encephalitis)
• Ischemic stroke or intracerebral hemorrhage
• Metabolic derangements

Refractory Status Epilepticus (If Seizures Continue Despite Above Measures)

Refractory status epilepticus is defined as seizures continuing despite benzodiazepines and one second-line agent—at this stage: 6

• Initiate continuous EEG monitoring 6
• Midazolam infusion is the first-choice anesthetic agent: 0.15-0.20 mg/kg IV load, then 1 mg/kg/min continuous infusion, with 80% success rate and 30% hypotension risk 6
• Propofol: 2 mg/kg bolus, then 3-7 mg/kg/hour infusion, with 73% efficacy but requires mechanical ventilation 6
• Pentobarbital: 13 mg/kg bolus, then 2-3 mg/kg/hour infusion, with 92% efficacy but 77% hypotension risk 6

Special Population Considerations

Febrile Seizures in Children:

• Simple febrile seizures: Follow local fever management standards and observe for 24 hours—do not give prophylactic antiepileptics 3
• Complex febrile seizures: Observe in inpatient setting with appropriate investigations 3

Women of Childbearing Potential:

• Avoid valproate if possible due to teratogenic risks 3
• Consider levetiracetam or lamotrigine as alternatives 1, 7